A coordinated Russian drone surveillance campaign targeted key military and nuclear locations across more than a dozen European countries between August 2024 and February 2026, according to a report published on July 2, 2026, by the London-based International Institute for Strategic Studies (IISS).
The Kremlin utilized its shadow fleet of sanctioned oil tankers to launch the unmanned aerial vehicles (UAVs).
The investigation tracked 144 incidents of complex reconnaissance drones flying over critical civilian infrastructure, airports, and military bases.
Among the targeted areas were RAF Lakenheath in the UK, France's Île Longue nuclear submarine base, and airbases storing US nuclear weapons in Belgium and the Netherlands.
Western militaries failed to capture or shoot down any of the intruding aircraft during the 15-month operation.
The report indicated that the UAVs exploited significant gaps in NATO air defenses, which are primarily structured to counter conventional military threats rather than low-flying, low-cost drones.
Analysts linked specific drone incursions to nearby Russian shadow fleet vessels operating with their transponder tracking devices deactivated.
In one instance, a sanctioned tanker named the Hav Dolphin was identified as the likely source of drones that monitored RAF Lakenheath in November 2024 and submarine bases in Germany and France later in 2025.
The IISS report noted that the mass expulsion of Russian intelligence officers from European capitals following the 2022 invasion of Ukraine had severely degraded the Kremlin's conventional spy network, prompting the shift to maritime-launched drone surveillance.
Researchers determined that the aerial operations utilized dark-sailing ships in the North Sea and Baltic Sea as deployment platforms.
Charlie Edwards, one of the report’s lead authors, described it as a coordinated approach.
The strategy allowed Russian intelligence to monitor Western logistics hubs and evaluate allied defensive reactions.
Edwards said the campaign operated with substantial impunity and represented tactical successes for the Kremlin but a strategic failure of allied defense.
European governments have generally downplayed the incursions and hesitated to issue direct public accusations against Moscow.
Edwards noted that every government they spoke to welcomed the report being published.
The report detailed that drone activities peaked in late 2025 before declining after European navies authorized the boarding and seizure of suspicious shadow fleet vessels in 2026.
It is highly likely that the Kremlin conducted a coordinated UAV campaign over Europe, the report stated.
The findings indicated that the operational methods were adapted from tactical lessons learned during the ongoing war in Ukraine.
The identification of two Russian private military contractors confirmed the militarisation of shadow fleet tankers as operational practice, according to the report.
The presence of Moran Security Group personnel on a seized shadow fleet tanker confirmed the direct involvement of Russia's main foreign military intelligence agency, the GRU.
Edwards said the pattern of sightings across 15 months and 13 countries cannot be explained by misidentification or opportunism alone.
The lack of a unified response from Western nations has exposed vulnerabilities in regional deterrence policies.
Russia has demonstrated repeatedly that it can penetrate the airspace of NATO member states, including over nuclear sites, without triggering a collective allied response, Edwards said.
The UAVs were described as large, hugely expensive, of military specification and flew for up to two hours over the Irish Navy ship LÉ William Butler Yeats.
European authorities are currently reviewing naval patrol strategies in international waters to counter the threat of maritime-launched drone incursions.
